South Africa's Supreme Court of Appeal (SCA) has handed down a murder conviction ruling on athlete Oscar Pistorius, replacing the initial culpable homicide sentence.

Five judges who heard the state's arguments last month unanimously agreed the Blade Runner should be found guilty of murdering his model girlfriend Reeva Steenkamp on Valentine's Day in 2013.

They ruled that he should have foreseen the deadly impact his four bullets would have in a small bathroom.

"He fired four shots through the door and he never offered an acceptable explanation... he fired not one, but four shots... that is exactly what the accused did," said Justice Eric Leach.

"I have no doubt that in firing the fatal shots, the accused... did foresee that whoever was behind that toilet door might die."

READ: Pistorius freed on parole after year behind bars

Culpable homicide

He is guilty of murder and the matter is referred back to trial court to decide sentencing.

Justice Leach described the High Court Judge, Thokozile Masipa's culpable homicide ruling as a "fundamental error".

"The trial misdirected itself as to the appropriate issue," said Justice Leach.

Pistorius and his family did not attend the one-day SCA hearing in Bloemfontein in November as he was under correctional supervision at his uncle’s Pretoria home.

Years in jail

They were also not in court Wednesday.

Law expert Zola Majavu said the SCA could decide to hear argument on an appropriate sentence, adding that it could also refer the matter back to the trial court to decide on an appropriate sentence.

The former paralympian faces at least 15 years in jail for murder. His defence team could prove that substantial and compelling circumstances exist to deviate from the minimum sentence.

“Even though there is a prescribed sentence, he may still convince the court to mete out a lesser sentence,” Mr Majavu said.

The legal team

Pistorius has already served a sixth of his five-year sentence and was released from prison on October 19. He recently reported to a nearby police station for community service as part of his sentence.

Meanwhile, the Pistorius family spokesperson, Ms Anneliese Burgess, has appealed to the media not to camp outside his home.

“I thought it best to let you know in advance that there will not be an on-camera statement made.

“We will consider the option of a short written statement – but this will only happen once we have had the time to confer with the legal team,” she said.